[PATCH] Reorder ZVCs according to cacheline

The global and per zone counter sums are in arrays of longs.  Reorder the ZVCs
so that the most frequently used ZVCs are put into the same cacheline.  That
way calculations of the global, node and per zone vm state touches only a
single cacheline.  This is mostly important for 64 bit systems were one 128
byte cacheline takes only 8 longs.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 824279c7884d557f3b2189e911d40f4c826fc08f..d15b1f68aef9de89a550d63bc4706a8e8a87eb3c 100644 (file)
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -47,6 +47,7 @@ struct zone_padding {
 #endif
 
 enum zone_stat_item {
+       /* First 128 byte cacheline (assuming 64 bit words) */
        NR_FREE_PAGES,
        NR_INACTIVE,
        NR_ACTIVE,
@@ -54,11 +55,12 @@ enum zone_stat_item {
        NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
                           only modified from process context */
        NR_FILE_PAGES,
-       NR_SLAB_RECLAIMABLE,
-       NR_SLAB_UNRECLAIMABLE,
-       NR_PAGETABLE,   /* used for pagetables */
        NR_FILE_DIRTY,
        NR_WRITEBACK,
+       /* Second 128 byte cacheline */
+       NR_SLAB_RECLAIMABLE,
+       NR_SLAB_UNRECLAIMABLE,
+       NR_PAGETABLE,           /* used for pagetables */
        NR_UNSTABLE_NFS,        /* NFS unstable pages */
        NR_BOUNCE,
        NR_VMSCAN_WRITE,

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 2386716f1754ed0867a9f6430dc3b7acd75ce8b7..2ee7ec5e003f78bba8a2de98c450d7dde807879e 100644 (file)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -447,11 +447,11 @@ static const char * const vmstat_text[] = {
        "nr_anon_pages",
        "nr_mapped",
        "nr_file_pages",
+       "nr_dirty",
+       "nr_writeback",
        "nr_slab_reclaimable",
        "nr_slab_unreclaimable",
        "nr_page_table_pages",
-       "nr_dirty",
-       "nr_writeback",
        "nr_unstable",
        "nr_bounce",
        "nr_vmscan_write",